This is a phase II trial of the I-131 labeled radioactive anti-B1 monoclonal antibody for the treatment of low grade lymphoma, as well as transformed lymphoma. Patients who failed prior therapy generally do not have substantial options, and in general have por overall outcome. The phase I trial of the radiolabeled anti-B1 demonstrated the ability to deliver 85 cGy whole body radiation with modest reversible toxicity and was associated with significant responses in patients with refractory low grade lymphoma. The current study looks at the dose of 85 cGy whole body radiotherapy in refractory low grade lymphoma or transformed lymphoma.